Research Of Electro-hydraulic Position Control System Based On High Speed On-off Valve

Electro-hydraulic position control system is one of the most important parts of the auto-control field, and it gets widespread application in the industry. With the development of the industrial automation, a combination of hydraulic technology, computer technology and electronic technology has been an inevitable trend. So, the digital hydraulic component appears. It can be controlled by computer directly and is delegated by high speed on-off valve(HSV).In order to study the problem that existed in the pwm control HSV, a set of electro-hydraulic digital control system with low cost and practical performance for rectifing device is brought forward by using common PC and universal data acquisition card, which is based on auto-control technology, and rectifing device that occupy small space and can conduct test easily is designed with corresponding electric control system.Two key technologies that can implement control system function on windows platform are studied:the multi-thread technology and the precise timing for real-time control system. How to adopt multi-thread technology to implement multiple tasks of control system is analysed, using high-resolution timer to fulfill real-time task of control system is discussed. By using Labwindows/CVI development tools, the design of application software of control system is fulfilled. Through the electrical-control experiment, signal filter experiment, digital PID position control experiment, this paper exams the practical function of the system, at the same time, it develops the idea of the design for electro-hydraulic digital correction system.The paper has a digital simulation analysis to pwm control hydraulic system. The simulation showed that the system’s response is rapid, the control is stable and precision, and strong adaptive capacity.